Chemical feed pump with improved valve means

ABSTRACT

A diaphragm or piston type chemical feed pump has an influent valve and an effluent valve connected to the pumping chamber each having in some combination a single or multiple ball check valve system. The valves of the pump are doubled and reversible within separable casings having oppositely disposed ball recesses so that the same set of parts can be assembled into an inlet or outlet ball check valve. For precise sealing, each valve has a resilient, self cleaning ball valve seat. Extensive testing shows a ball diameter of five-sixteenths or 0.3125 and a hole diameter of 0.190 + OR - 0.006 to be the optimum ball to hole diameter combination. Additional testing shows that the ball to hole diameter can be scaled up or down in proportion for larger or smaller pumps with greater or lesser flows.

United States Patent [151 3,

Hussey 1 May 9, 1972 54] CHEMICAL FEED PUMP WITH FOREIGN PATENTS ORAPPLICATIONS IMPROVED VALVE MEANS 987,921 4 1951 France ..137 539 [72]Inventor; Norman Hussey, mmburyv 337,339 10/1930 Great Britain ..137 512[73] Assignee: A & D Fabricating Company, Inc., Lowell, primary E i -S lB Rothberg M Assistant Examiner-David J. Zobkiw [22] Filed: y 25 1970AttorneyPearson & Pearson [52] U.S. Cl ..l37/269.5, 137/512, 137/533.l3,l37/533.l5 [51] Int. Cl ..Fl6k 15/04 [58] FieldofSearch..137/269.5,27l,5l2,5l2.2, 137/539, 539.5, 533.11, 533.13, 533.15

[56] References Cited UNITED STATES PATENTS 2,707,485 5/1955 Saalfrank..137/512 3,399,694 9/1968 Vinson ..137/512 2,922,432 l/l960 Huntingtonet a1. ..l37/269.5 3,000,320 9/1961 Ring ....l37/512 X 3,081,730 3/1963Dvorachek. ....l37/5 12 X 3,084,709 4/1963 Flick et a1. .l37/269.5 X3,415,271 12/1968 Maasberg et al ..137/512 [5 7 ABSTRACT A diaphragm orpiston type chemical feed pump has an influent valve and an effluentvalve connected to the pumping chamber each having in some combination asingle or multiple ball check valve system.

The valves of the pump are doubled and reversible within separablecasings having oppositely disposed ball recesses so that the same set ofparts can be assembled into an inlet or outlet ball check valve. Forprecise sealing, each valve has a resilient, self cleaning ball valveseat.

Extensive testing shows a ball diameter of five-sixteenths or 0.3125 anda hole diameter of 0.190 I 0.006 to be the optimum ball to hole diametercombination.

Additional testing shows that the ball to hole diameter can be scaled upor down in proportion for larger or smaller pumps with greater or lesserflows.

1 Claims, 4 Drawing Figures CHEMICAL FEED PUMP WITH IMPROVED VALVE MEANSBACKGROUND OF THE INVENTION In the chemical feed pump art, sealing ofthe fluid being pumped is essential, to avoid leakage or contamination,so that diaphragm pumping chambers are often used to assure sealing. Formaximum efficiency the inlet valve must not permit back pressure, theoutlet valve must not permit back flow, and the valves must be asperfectly sealed as the diaphragm pumping chamber, or the value of thelatter will be lost.

Chemical pumps often are used with liquids which are corrosive, or tendto plug the passages. It is therefore necessary to use pump parts ofinert materials, and of precision fit, to avoid leakage and plugging andto avoid the necessity of breaking the seals to clean out the interior.

SUMMARY OF THE INVENTION In this invention, ball check valves ofimproved structure are provided, .the resilient, annular ball seatsbeing of predetermined durometer for the correct resiliency which willpermit the ball to seal in the seat even in he presence of slightaccumulations of foreign matter on the ball or seat. Depending on theselected durometer, which is preferably about 55, the valve port isdimensioned at a predetermined inside diameter based-on a proportion ofthe outside diameter of the ball. In addition, the ball valve means ispreferably reversible and doubled with two balls, two ball seats, and aspacer so that the same set of parts can be assembled into a doubledinfluent valve or a doubled effluent valve.

Ease of replacement, lessening of parts inventory, lower cost ofmanufacture, and more efficient pumping all result from the use of thedouble ball check valves of the invention with them predetermineddimensions based on the required resiliency or hardness of the valveseats.

BRIEF DESCRIPTION OF THE DRAWING FIG. I is a plan view in section online 1l of FIG. 2;

FIG. 2 is a side elevation, in section on line 22 of FIG. 1, of a pumpconstructed in accordance with the invention;

FIG. 3 is an enlarged fragmentary side elevation, in half section, of aneffluent, or exhaust, valve of the invention; and

FIG. 4 is a view similar to FIG. 3, showing the identical parts reversedto form an influent, or intake, valve.

DESCRIPTION OF A PREFERRED EMBODIMENT In the drawing, represents atypical chemical feed pump, well known in the art, and which includes anelectric motor 21, gear reducer 22, and drive shaft 23, journalled inbearings 24 and 25 in the walls of the pump housing 26. An eccentricrotor 27 having a freely revolvable bearing race 28 is fast on shaft 23and rotates within a yoke 29 to convert the rotary mo.- tion of shaft 23to reciprocal motion of yoke 29.

The travel of the reciprocating stroke of yoke 29 is controlled by thedial 31, and threaded dial shaft 32, the latter preferably beingarranged so that ten full turns will adjust from zero to about one-halfinch, the latter being full output. Thus the pump is easy to rate in percent of output by turning dial 3], and its indicator 33, to zero, 10,20, 30, etc., thereby indicating and setting the output of the pump 20.

The yoke 29 is fixed to a rod 34, encircled by coil spring and fixed atits other end 36 to the center of the flexible diaphram 37.

The diaphram pumping chamber 41 is defined by the diaphram 37 and thetransparent cap 42, tightly sealed to housing 26 by machine screws 43and reinforced by cross flanges 44. An influent conduit 45 is formed incap 42 to connect chamber 41 with the influent, ball check valve means46, and a similar conduit 47 connects the chamber to the efiluent ballcheck valve means 48.

The influent valve means 46 is substantially identical with the effluentvalve means 48, using the same set of parts, in-

eluding a main casing 51, having a portion of reduced diameterexteriorly threaded at 52 for threading in a threaded hole 53 or 54 incap 42, and having a ball chamber 55 terminating in interior threads 56.An end closure 57 is exteriorly threaded at 58 to engage the threads 56and mutually define the chamber 55 in the valve, the inlet and outlettubes, carrying the fluid to be pumped, being affixed to the end closure57 in any convenient manner, such as by threaded clamping of a member 59on threads 60.

The terminal tip 62 of each member 57 includes an annular recess 63 foran O ring seal 64, as well as including an axial fluid passage 65, andthere is a similar axial fluid passage 66 in the casing 51. Theoppositely disposed fluid passages 65 and 66 are of sufficient diameterto each form a ball recess which permits the parts to be reversed.

Each valve means includes at least one spherical ball 67, and oneannular ball seat 68, which may be entirely of resilient material, ormay be of metal with a resilient insert 69, for seating the ball, and acentral, cylindrical axial bore 71, forming the valve port, the seat 68also having an annular peripheral groove 72 for an O ring seal 73.Preferably a second ball 74, a second seat 75, plus a hollow cylindricalspacer 76 are provided in each chamber 55 in tandem with ball 67 andseat 68 to form a double ball check valve. As shown in in FIG. 4, theidentical parts may be used to form an influent ball check means, sothat the valve means are reversible. The double ball and seat assuresprecision, efficient pumping with little chance for back flow, leakageor misfunction due to a single seat becoming corroded or fouled withforeign material, sediment, or the like.

. I have discovered that an annular ball seat, such as 68 or 75 shouldbe of, or should have an insert seat 69 of, resilient, yieldablematerial such as rubber, neoprene, or the like, having a durometer ofabout 55 to effectively permit the ball to seal even in the presence ofsediment on the seat or ball. I have further discovered that the insidediameter of the bore portion 71, of the seat should have a predeterminedrelationship with the outside diameter of the ball 67 or 74, forexample, when the outside diameter of the ball is 0.3125 inches, theinside diameter of the bore should be 0.190 :t 0.006 inches. Thesediameters should be scaled up or down in proportion, depending on thebore diameter, the durometer of the seat remaining at about 55 to avoidslag build-up on the seat.

In the embodiment shown, the annular seat is about oneeighth of an inchin thickness, durometer is 55, the CD. of the ball is five-sixteenths ofan inch, or 0.3125 inches, and the inside diarneter of bore, or port 71,is 0.190 t 0.006 inches in accordance with the formula set out above.

Preferably the annular seat 69 does not have the conventional truncatedconical countersink, but instead the bore 71 is cylindrical and themouth, or inner peripheral nm 70, is a sharp-edged circular support forthe ball.

I claim:

1. In a chemical feed pump of the type having a diaphragm, or piston, apumping chamber, and influent and effluent valve means connected to saidchamber, each valve means including a double ball check valve in tandem,the improvement comprising:

a pair of identical, separable casings, each having a cylindrical valvechamber therewithin containing one of said double ball check valves intandem;

each ball check valve including a spherical ball of predeterminedoutside diameter and an annular ball seat of resilient material, ofpredetermined durometer of about 55, said seat having a sharp edgedinner peripheral rim seating said ball and having a cylindrical, centralaxial bore forming a valve port, the outside diameter of said ball andthe inside diameter of said port being in the proportion of 0.3 l 25 to0.190 1 0.006;

a hollow cylindrical ball receiving spacer within each said valvechamber, one of said balls and ball seats being at each opposite endthereof, within said valve chamber, and each ball seat being identicaland reversible within said valve chamber;

each said separable casing including a main casing and a threaded endclosure and each having an axial fluid passage of sufficient diameter toform oppositely disposed ball recesses permitting said influent andeffluent valve means to be formed by identical structure.

at a! n-

1. In a chemical feed pump of the type having a diaphragm, or piston, a pumping chamber, and influent and effluent valve means connected to said chamber, each valve means including a double ball check valve in tandem, the improvement comprising: a pair of identical, separable casings, each having a cylindrical valve chamber therewithin containing one of said double ball check valves in tandem; each ball check valve including a spherical ball of predetermined outside diameter and an annular ball seat of resilient material, of predetermined durometer of about 55, said seat having a sharp edged inner peripheral rim seating said ball and having a cylindrical, central axial bore forming a valve port, the outside diameter of said ball and the inside diameter of said port being in the proportion of 0.3125 to 0.190 + OR - 0.006; a hollow cylindrical ball receiving spacer within each said valve chamber, one of said balls and ball seats being at each opposite end thereof, within said valve chamber, and each ball seat being identical and reversible within said valve chamber; each said separable casing including a main casing and a threaded end closure and each having an axial fluid passage of sufficient diameter to form oppositely disposed ball recesses permitting said influent and effluent valve means to be formed by identical structure. 